You didn't say if you're breastfeeding or formula feeding - if you are breastfeeding exclusively, then mustard yellow and liquid poos are normal. My boy had a period when he produced at least one poomaggedon per day. Now it's settled but we will see what the future holds.
My EBF little does this every morning without fail. I know it’s the biggest poo he ever does but I also know it’s him fully emptying his bowels. I’d say as long as it’s normal in colour you should be fine. I can sit next to my little one for a good 5 minutes getting him to push and trust me you can hear it😅x
My little girl does this, we might as well buy shares in Vanish 😂
Yes this is very normal this means they’re having healthy bowel movements as longs as it yellow whilst your feeding him milk. You should only be concerned if he starts to have a watery poo several times a day because this could lead to dehydration. Trust your gut if you’re worried ask health visitors or visit gp x