Babys morning pee is very dark

Lindsey-Rae • 29 years old ✌ RJB 10/20/13 ❤ Julien-Dean 11/9/2017 💙

My 9 week old sleeps through the night (8-9hrs on average). Lucky I know!! But when I open his diaper in the mornings his pee is very dark. Almost an amber color? This is the only time of day that it looks like this. Otherwise it's pale yellow or clear... Any ideas? He seems totally fine otherwise. Eating well and happy...