We've had the Gro clock for less than a week, and fingers crossed our boy has slept through 6/7 nights! We've had a terrible time recently, with him waking for a number of hours in the middle of the night.
He's 2.5 and has never been a great sleeper. We night weaned him about a month before hoping that might help and it did a little.
Our problem was that he wanted us to read/play/take him to the potty/get him a drink etc etc.
I thought we could give the Gro Clock a Go, the first couple of nights we read him the story and set if for 7, he said goodbye to the sun, he got the idea straight away. 7am was wishful thinking! He didn't disturb us in the middle of the night, but got up before the sun came out. So then we decided to go for 6am when he seemed to wake up naturally, combined this with a star chart and it worked. We're hoping that once it gets established we can creep the waking time forward so we can get a bit more of a lie in!
Thank you Gro Clock!