My girlfriend lives in another city, far enough from where I stay to make planning visits a necessity. These usually happen over weekends. For reasons known only to herself, she insists on bringing her 19-year-old son along, even though I've subtly tried to dissuade her from doing so in the past. He then stays over at her brother's place. (And maybe this insistence on bringing him along, is a red flag in and of itself.) The son seems to be ambitionless and employed by his biological dad on a part-time basis.