Well the bowel movement of.children totally depend upon what they eat and the amount of water they are taking in.
If the food that you are giving you children is to thick and difficult in swallowing then it might be very difficult to the baby to digest it and it may be difficult for him to defecate too.
Food that we feed children should have enough dietary fiber so that they may not face the problem of constipation. Foods that are high in diet fiber are cucumber, carrots, leafy vegetables, ckickko fruit, beans, banana etc can be given after boiling or raw vegetables can also be given after thorough wash. Can be given directly or given in mashed form.
Apart from this he need to take adequate water so that the stool get softened and get deprecated easily.