Help! Great Tit Fledgling

Hi,

We have been watching a family of great tits with a camera in our nest box for the last couple of weeks and today they all started to leave the nest! There’s 7 in total and so far 6 have left.

1 is left in the box currently and isn’t chirping a lot, although it does chirp occasionally but not as much as the others did. It hasn’t made any effort yet to leave. It does occasionally flap or stretch its wings  

It has only been about 30mins since the 6th bird left the nest and so the 1 left might still fledge soon! But all 6 left very quickly after each other, with the mum calling them. Now the mum is no longer calling (or doesn’t seem to be) and has flown away with her other babies. So I just wanted to ask, just in case, what I should do if the baby is left in the box all day? Or how long should I wait before intervening? 

I have no intentions of intervening unless it’s absolutely necessary for the survival of the bird because I want to allow nature to take its course and I hope the baby will fledge on its own. But last year we were watching a family of great tits again, and randomly while they were still so young the parents abandoned them and didn’t come back, and we didn’t know what to do so unfortunately they all died before we had time to take them anywhere to be rescued. So I would just like some advice about this 1 bird who is left please as I don’t want the same sort of thing to happen to it! 

Any advice would be greatly appreciated. Thank you!

Posted at 8:47am. 

Edit at 10:36am: the bird made an attempt to leave I think. It flew up to the hole in the birdhouse and spent about thirty seconds peering out of the hole. It is also chirping more. I think it will be fine and I was worrying for nothing but I will still keep an eye on it! 

Edit at 10:59am: the bird left the nest, unfortunately it landed on the grass and then ran under some decking we have and we don’t know how to get it out so we’re just going to keep an eye on it and hope it comes out :(