"She's walking, maybe a little too fast", she said.
Also, the chance to demonstrate that she is still the very best in the business.
The sheer energy it took to stay with the 25th seed eventually took its toll, though, and Williams was ruthless in converting.
"It's insane. I don't even know how to feel because I literally didn't think I'd do this well in my fourth tournament back", Williams said.
Alexis Ohanian, co-founder of Reddit, watched on as wife Williams triumphed in her semi-final on Thursday, beating Julia Goerges 6-2 6-4 in one hour 10 minutes. Kerber defeated Williams in three sets to win the Australian Open in early 2016, but Williams answered right back just months later, defeating Kerber to win her seventh Wimbledon title.
Goerges could only find the tram lines with a forehand down the line as Williams forced the first break, and a swirling cross-court forehand proved too hard for her to return as the first set went the way of the imperious American.
"I had age [in common with Williams] and a C-section, and I certainly wasn't coming back to play tennis", said Shriver, who's at Wimbledon as an ESPN analyst.
Williams will face another German, 11th-seeded Angelique Kerber, on Saturday in a rematch of the 2016 final at Wimbledon.
"I don't want to limit myself", Williams said.
Kerber used a seven-game run to seize control of her semifinal and collect a 6-3, 6-3 victory over the 12th-seeded Ostapenko. Kerber did not dictate much, content to let 2017 French Open champion Ostapenko determine the outcome of almost every point. By the end, Ostapenko had far more winners, 30-10, and far more unforced errors, 36-7. Williams won that for a second consecutive Wimbledon title, then sat out the grass-court tournament past year while pregnant, part of a 16-month gap between majors.
The couple announced the birth of daughter Olympia in September. I lost count after, like, four surgeries because I was in so many surgeries.
Two months ago she withdrew from her French Open last 16 match against Russia's Maria Sharapova due to health problems just hours before the encounter was planned to start.
In a sense, Williams has been writing this narrative - rising up, overcoming, doing the impossible - since her father, Richard, took her and sister Venus to a dilapidated tennis court in Compton, Calif., put rackets in their hands and coached them, along with their mother, into champions. "This was not inevitable for me". It was tough. There was a time where I could barely walk to my mailbox.
After taking tentative steps in her return to the sport in which she has always been the dominant force, just 13 matches into her comeback and ranked 181st in the world, she appeared to be working at the level that enabled her to win 23 Grand Slams.
It was the first time at these championships that the American had faced a player ranked in the top 50 and she stepped up with a powerful display that also showed better movement around the court than in previous rounds. Or, more to the point on this afternoon, how such a stinging serve and big groundstrokes didn't help her avoid first-round exits each of the past five years at Wimbledon.
Kerber has her heart set on winning a first Wimbledon title after booking a return to the final.
"She brings her "A game" in a lot of important moments", Goerges said. Goerges, playing her first Slam semifinal, sent a forehand flying wide off the sidelines to concede serve.
"I'm glad no one told me at the time I was going through that".
Nearly inevitably, Williams gained a third break to charge to a 5-2 lead before showing her first signs of nerves to drop serve for the only time while trying to close out the semi-final.
"Oh, wow. I never thought about that. For me, I only see joy out of it", Williams said with a smile.