Help! 6 mth old awake for hours in the night

[tasmaniandevilchaser]

My 6 mth old DS has never been a great sleeper but I'm at the end of my tether now. He's awake in the night regularly for at least 2 hrs, usually more, up to 5 hrs. He knows day from night , he sleeps much less in the day. Maybe 3x 30/45 min naps.

I don't want to do sleep training but I can't cope like this. Why is he doing this? If I could even understand it I might feel less desperate. Any ideas?
Tia

Bump!

My Ds does this, I haven't quite worked it out but I think its to do with being overtired. Can you try to get him to sleep longer in the day? I am walking miles with my ds at the moment as the only place he will sleep a decent stretch is in the buggy but that and not too long between last nap and bedtime seems to help.

Thanks hamnvik , I had wondered about over tiredness. Last night it was only 1 hr 45mins between wake up from last nap and getting into his cot and we had a bad night. But I think avoiding over tiredness is a good principle to go by! Hopefully it will sort itself out but I think we will end up sleep training before then. The night he was awake for 5 hrs was so horrifying I can't do that again.

Lengthening naps is really hard, I'm so shattered I can't traipse the streets ( he's a buggy sleeper too), I'm supposed to be 'sleeping when he's sleeping'!