Jack is 5 months old and i've noticed that for a while now he is making loud straining noises and stiffening his legs, often during feeding. He's not constipated - he does it all of the time, even after a poo. He doesn't seem upset or angry when he's doing it so i don't think it's because he's in pain or anything. It's just not nice to see and makes feeding more difficult as he's constantly wriggling and going stiff. Anyone else had experience of this? x