Some people swear by a Tena pad inside the nappy for extra absorption. I used to have to change DS 1-2 times overnight.
I then found that fleece longies were a godsend overnight. However I live in the land of a kazillion degrees and he wasn't tolerating wool shorties so I'm really glad he's weeing less ATM.
Even thicker polar fleece trackies will do the same job.
I have always used wool covers over the top at night. Wool is the most regulating fabric you can get so the baby will not get hot, it wicks the moisture away and then evaporates so it won't pool in the pants like other covers. It has natural antibacterial qualities which means no need to wash, just air and sun, unless they poo on them!! Wool covers all the way!
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