It is from this news article. The context is that Mr Trump asks a child if he believes in Santa.
Footage of the incident circulating on social media shows Mr Trump then telling the boy: "Because at seven, it's marginal, right?"
Does Mr Trump mean that Santa is not important to a boy of 7?
I think so, "Mr. Trump means that Santa is not important to a boy at 7"
The following evidence from here is acknowledging it:
Trump tells boy that believing in Santa at 7 is 'marginal'
WASHINGTON (AP) — President Donald Trump and first lady Melania Trump took calls from children anxious to find out where Santa is on his gift-giving journey.
In one conversation, Trump asked a 7-year-old named Coleman, "Are you still a believer in Santa?" He listened for a moment before adding, "Because at 7, it's marginal, right?" Trump listened again and chuckled before saying, "Well, you just enjoy yourself."
Mrs. Trump told a caller that Santa was in the Sahara. Several minutes later, she reported that Santa was far away in Morocco but would be at the caller's home on Christmas morning.
Mrs. Trump later tweeted that helping children track Santa "is becoming one of my favorite traditions!"
The NORAD Tracks Santa program became a Christmas Eve tradition after a child mistakenly called the forerunner to the North American Aerospace Defense Command in 1955 and asked to speak to Santa.
First, Mr. Trump has asked:
"Are you still a believer in Santa?"
Then he has said:
Because at 7, it's marginal, right?
Apparently, Mr. Trump meant that Santa is not important to a boy at 7!
