It's far easiest to have minimum cabin luggage when you are looking after kids. Think backpack.
Get hubby to check in one bag with all your clothes etc. And put food and entertainment in backpack. That way he can put toddler in carrier and either hold your eldest by his hand or carry him on his shoulders.
Yes I have previously done it with one kid on my front and one on my shoulders.
wifey of hubby who is always away. mother of two girls who are always amusing.