Until she spotted the cute toddler's famous father, that is.
Much was made of the fact that Molly's little son Brooks had a VIP play date with Harper on 10 September, when the two little ones were pictures at a park with Molly and the footballer.
At first, though, Molly didn't click as to who her little boy had struck up a friendship with as he played in the New York park.
"I'm like, 'Who is he talking to? Who is he playing with? And, yes, he was with Harper Beckham," Molly recalls. "And, David Beckham is the nicest guy . . . I even said, 'Oh my god.' I didn't realise it was her!"
Molly and Brooks with her husband, movie producer Scott Stuber
Speaking to Us Weekly, she added: "You never know who you're going to meet. I mean it was literally like 95 percent humidity and it was like 100 [degrees] and there I was like, 'Oh, hello Mr Beckham!' But he is such a nice guy and a good dad."
Molly welcomed 14-month old Brooks in June 2012. He is the first child for the 40-year-old beauty and her husband, movie producer Scott Stuber.
The couple may be ready to add to their family, after Molly recently revealed she would like "more baby Brookses", and she needed to "start on that path".