Child with hearing problem

Hi, I’m a newbie here. I don’t know whether this is the right place to ask this question. If not please excuse. My child is having a hearing problem. Me and my wife are both working and our child will be alone at home after her school. We are afraid about her safety. What shall we do to make her.Due to the problem in hearing she cannot pick up the call when we make a call. We are planning to install a security system and consulted csp alarms for the work but don’t know which type of a security system will suit us. Please give suggestions. We need a cctv setup which can be connected to our mobile phones and what all additional features shall be included? Thanks in advance