Not if it's something related to the work environment which could be changed and the TM wants to work more hours. But if it's just nosiness into the TM's personal life, then it's not an okay question.
Maybe a better way to put it would be, "Hey, would you be interested in picking up more hours on a regular basis? You're really on top of your area [or whatever the TM does], and it'd be great to give you more hours if you're interested."