I had this problem with Baz when I first got him from rescue - our first walk together was a total nightmare as he only had a harness and he's a large GSD and I'm only small.

Short term a Halti or Gentle Leader (which I've found to be better) will give you control of him. Try playing ball with him before you take him out to knock the edge of that energy (throwing a ball up the stairs so he has to run upstairs to get it is quite energy consuming) and don't let him go through the door until he is sitting quietly and calmly.

As you're walking keep changing directions so that he has to stick close to you - Baz very quickly became convinced I was a totally unreliable walker, lol! Also try taking a favourite toy or treat with you to focus his attention on you, labs are usually very food orientated. Each time he comes when you call him give him a treat (you can do this in the house to start with) and remember never to scold him if he doesn't come back straight away otherwise he'll associate coming back with being scolded. Some dogs seem to respond better to "let's go" and turning your back on them and walking away.

If you're worried about giving him too many treats just use part of his daily food ration but your son and dil really need to continue with this on their return otherwise you'll have the same problem if you have to look after him in future.

Good luck and let us know how you get on - I vividly remember that first nightmare walk!

J