The New Slang
We are not certain whether this mom is that cool to invent a brand new slang or it was just a mistake in the Christmas spirit, as she was asking him to come on Christmas. Whatever it was, the son seemed to understand it without needing any more explanation.
This is a very Santa-ish way of asking someone to join you for Christmas, but it sure seems to work too. Although it is quite interesting, not everyone would want to get a message from their mom asking them to “Ho” with them, it just feels awkward.