13 month old "good sleeper" suddenly up for 2-3 hours in the night HELP!

[FrazzledFairyFay]

My 13 month old DS was, until about a month ago, a really good sleeper. He still goes down for his naps and to bed without a murmur but has started waking up for 2-3 hours during the night. We are sleep-deprived and at the end of our tethers.

He seems to have a gurgly tummy but we've tried gripe water and infacol and endless winding and it doesn't seem to help.

We've tried cuddling him to sleep, which sometimes works.

We've tried 'controlled crying' but he never stops

We've tried re-running the bedtime routine, to no avail.

Does anyone have any ideas? He's been awake since 10 tonight and I just cannot get him to settle.

Dd did this whenever she had teeth coming through, particularly the back ones. We would get weeks of it before we could actually see any teeth, and then a tooth or two would suddenly appear. Could it be that?

I really hope it is teeth but it has been going on for weeks. He was up from 10:30pm-2:30am last night. And he's already woken up tonight - Dh is dealing with him. I am just praying it's a phase and will pass as I'm shattered and need some sleep.

Is he having anythig new in his diet? Bananas of all things do this to my ds.

No, nothing new to eat. He's still awake . He's absolutely fine during the day, goes down for naps fine, goes to bed without a murmur and wakes up perfectly hapilly - he's just miserable during the night. I have no tether left.

Is it worth giving him a dose of calpol when he wakes at night to see if that works? If it does, then something (possibly teeth) might be hurting him.