The Keyword is “Boy”
When you’re in a massive store like a Walmart, and one of the members of the relationship has a dead phone, it’s important for the two of them to stick together. If they lose each other in a store as big as Walmart, then good luck to them finding each other.
Aly must have forgotten to let her boyfriend know that she was going to the bathroom. A few minutes later, she was walking down every aisle looking for him when she suddenly heard over the intercom that her child was at register 10. This is a very funny joke unless her boyfriend is admitting that he’s a child.