BLOOMINGTON, Minn. — Zach Ertz left the Eagles' Dec. 3 loss at Seattle with a concussion, after a collision caused his head to slam hard into the CenturyLink Field turf as a pass fell incomplete. At home in Northern California, Lisa Ertz's reaction was visceral.

"I was crying on the floor of my kitchen," Lisa Ertz, mother of the Eagles' Pro Bowl tight end, said Friday. "It was hard to see and terrifying. It's the part of football that's the worst part, the most terrifying part."

Any NFL mom might react this way, with more and more research indicating the long-term dangers of football head injuries. But Lisa Ertz has seen another of her four sons, Shane, have to give up football after suffering multiple concussions in high school, including one in which he was knocked out cold for several minutes. In the wake of that ordeal, she became president of the VICIS Foundation, which promotes and funds safer football equipment, including a helmet that gives slightly upon impact, which the NFLPA has rated the safest on the market.

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Zach Ertz – whose mother calls him "Zachary," by the way – was not wearing the VICIS helmet when he suffered his concussion, which cost him the next week's game at the Los Angeles Rams. A VICIS spokesman said 60-plus players on 18 teams used the helmet in 2017. Many, including Ertz, tried it on and found the fit and feel too different from what they were used to.

The model available in 2017 training camps weighed nearly a pound more than a traditional helmet, though Lisa Ertz, in Minnesota to watch her eldest son in Super Bowl LII but also to promote VICIS, said the newest model is lighter.

"I wanted my child's beautiful head in here, but he's also 27 and he's going to make his own decisions," she said.

Dealing with Zach and other players on this matter has led her to the conclusion that the best way to get the helmet into wider use is to get high school players using it. Athletes are creatures of habit, and this extends to their equipment.

"If we get these kids in the helmet in high school, then this becomes their piece of equipment their whole lives," Lisa Ertz said. "The outer shell is very similar to a bumper on a car. It absorbs the impact of a hit. We never say that it's concussion-proof," but players who use it have said they feel fewer effects from hits to the head.

Lisa Ertz was born in Pittsburgh, grew up a Steelers fan, went to Cedar Crest College in Allentown, and married Doug Ertz, a Lehigh fullback, though they have since divorced. The fact that Zach is preparing to play in the Super Bowl as the Eagles' leading receiver, with 74 catches for 824 yards and eight touchdowns, is largely due to her influence, she and her son agree.

"My seventh-grade year I played football. I was, like, 15 pounds overweight, so I had to lose a ton of weight," Zach Ertz said this week. "They put me at left tackle, they put me on the defensive line. I absolutely hated football. I didn't want to play again. Eighth grade year I didn't play.

"Then my freshman year in high school, she wanted me to go out again, so I could make friends. It wasn't so I could have success, it was just so I could make friends on the team. Going into [Monte Vista High in Danville, Calif.,] that's all she wanted me to do, so I could feel comfortable."

Lisa Ertz said her son originally aspired to be a basketball star, but eventually realized the route to free college was through football. She took control of Zach's college choice, as well.

"UCLA and Stanford were the final two. I didn't know at the time if I was going to get into Stanford … UCLA was kind of always knocking on the door," Zach Ertz said. "By the end of it, I was kind of 'I want to go to UCLA.' And she shut that door real quick – she said, 'You're going to Stanford.' I think she understood the post-college opportunity when you go to Stanford. Being from the Bay Area, the alumni network is extremely strong there."

"I was very adamant and I actually said to him, 'Well, it's not like you're going to play pro football.' Go get a great degree, have a wonderful experience, and the rest of your life, you can say you went to Stanford," Lisa Ertz recalled.

Zach Ertz got that degree, in management science and engineering, but along the way he got to catch passes from Andrew Luck and become a top NFL prospect, even as younger brother Shane had to give up the sport.

"The violence, the danger, it has definitely enabled me to be a football mom on a mission," Lisa Ertz said. "I'm going to take this platform and I'm going to make the game safer. I don't want to see it go away – I don't … It unifies this country in a way nothing else can.

"I do think that much more can be done to help make it safe, so that mothers can tell their boys, 'Yeah, you can play.' I feel comfortable with that. This [helmet] is a game-changer, it's a lifesaver, really."

The VICIS Foundation provides grants to schools to promote football safety. "It could be helmets, it could be shoulder pads. It could be training for coaches who aren't up on best practices for tackling," Lisa Ertz said. "Not every high school has access to that stuff."

Lisa Ertz, who formerly was an office manager for a law firm, enjoys seeing her son prepare to play in the Super Bowl, but she also enjoys her new role.

"I get to talk about football and football safety all day," she said. "Helping schools across the country get access to the money we're trying to raise for them. Get athletes to support the foundation by seeing what we're doing."

Last year, Zach married USA Soccer's Julie Johnston, creating one of sport's highest-profile couples. That, too, has been fun for his mother, though the concept of such widespread fame still seems odd.

"When you're with Zach and Julie, not in a million years would you think they're who they are, until someone will come over and ask for a picture. You're like, 'Oh, yeah.' They're so normal. It's really amazing."

Lisa Ertz said she was thrilled Friday to see Terry Bradshaw, an idol of her youth, and Brian Dawkins.

"That's one of the reasons all of this is so amazing to me … I'm thinking to myself 'That's how younger people see my son.' I don't see it. He's just my normal, pain-in-the-neck kid."