Oo normal lang yan, lalo na pag stressed, sleepy, o gutom ang baby, ang hilik nila ay parang way nila to communicate, kasi sobrang liit pa lang ng vocabulary nila sa age na yan. A few of us mums noticed na mas madalas ang hilik pag transition period like from play to sleep or pag may bagong tao sa paligid, so don't worry too much about it. If it's excessive though and may kasama pang ibang signs like fever or hindi kumakain ng maayos, then maybe check with your pedia just to be safe.