Hiya, I have a similar issue with my DS (5 months old). I tried one of the suggestions from "No Cry Sleep Solution", which is to do something nearby/wait for them to wake up (e.g. my son has a 45 min sleep cycle so I would go into the room and wait at about 40 mins) and then as soon as they stir, to start doing what you did to get them to sleep in the first place. In my case this was breastfeeding him and patting his back. This did seem to work for me for a while but often he would wake up still and take 20 mins to go back down.

Lately it has been getting more and more difficult to resettle him and I was getting very cranky trying so I stopped doing it. He has "slept through" his cycle a few times- having a 1.5-3 hour sleep- but only does this maybe once every 2-3 days. Today he just had 3 x 45 min sleeps but was really cranky at bedtime. Other days he seems to cope ok. He sleeps ok at night (well, he wakes up several times but not every 45 mins at least!) I've been trying to decide whether to keep persisting and trying to get him to sleep more or whether it stresses us out too much to do that. I'd be interested to hear what others say!

You could try the NCSS suggestion above and see if it helps?

I have a copy of No Cry Nap Solution coming so will see what that says!

My DS rarely wakes crying, he usually wakes very happy and chirpy which is why it is so hard to get him back to sleep.