Child leaving house all hours of the day and night

[spenicky]

My sister recently lost custody of her grandson because he keeps leaving the house in the middle of the night and during the day.  He does this constantly.  She has has placed alarms on the doors, numerous locks, and whatever else you can think of.

My question is this:  Why does he continue to do this?  Even while in foster care he continues to escape.  When asked why or where he is going, he has no substantial answer.
He is 4 1/2 years old and has been in and out of foster care since birth.  Is this a behavior problem or a psychological problem? An attachment disorder?  I have been searching the internet for anything that is closely related to the problem and I can't find anything.  CPS appears to baffled as well.

Obviously she can continue to safe guard the house so that he can't get it, but I feel that as he gets older it will just intensify if we don't find the real reason behind why he is doing this.  

I'm not looking for a straight answer, I am looking for some suggestions into what might be wrong with him so that we can help him.

Thank you for your time,

[AUSTIN431]

wow scary when i first started to read it i thought he was a teenager till you got to his age has anyone tried following to see where he goes? i would think that being in foster care since he was young would play a big part in this has he gotten any counselling? Did he develop a close relationship with his grandma or did he keep his distance ? i'm sure kids who have been in foster care have trouble bonding with people and he probably never really felt like anywhere he was is actually home how could he when he gets moved around so much . I suggest he gets therapy and that someone follows him around a few times and see where he goes it might answer some questions about why he needs to leave all the time and it could help with his therapy too. I hope his grandma gets to see him still he needs time to realize she really wants him and wouldn't abandon him

[AnnieBrooke]

Is there any counseling help that he gets?  A children's therapist?  If my son did this (he's 4 1/2) it would be really surprising to me because usually he's right at my heels, wanting attention.  So I would think he was trying to get away from something painful, more painful than his need for love from me.  Do you know anything about his daily care, and how loved he feels, and how much attention he gets?  Do you think he's looking for his mom?