this sentence does not make sense to me. Does it mean: Are you leaving the girls? Why not : An bhfuil na calini agat?
No, “Do you leave the girls?” is not the same as “Are you leaving the girls?”. In Irish, the former sentence has a habitual aspect, while the latter sentence would have a progressive aspect — that is, “Do you regularly leave the girls?” (e.g. after taking them to the park, you typically leave them there while you go to purchase a newspaper) vs. “Are you leaving the girls now?” (e.g. so that you can get some sandwiches for them this time while they’re playing in the park).
An bhfuil na cailíní agat? means “Do you have the girls?”.