We have recently had my dh's dd (15yo) come and live with us. We also have 2 dc. Since dsd has come to stay with us she is eating anything and everything. We cook home cooked meals every night and dsd has same size portion as me and dh. So dont think she's still hungry, she's either greedy or has a sweet tooth. She has eaten 7 penguin bars during the night that the next morning ive had none to put in dc's lunch boxes for school. The other night, we woke up to 3 empty biscuit packets in the bin. She had eaten 3 packets while we were sleeping. We bought a ben and jerrys ice cream for the family to share and she ate the whole tub on her own. She just keeps eating and eating. But she claims it's not her. Ive stopped buying biscuits but she's eating the stuff for the sandwiches, even down to eating all wraps or all the tuna/cheese. I cant understand why she's eating so much. We've spoke to all the children about it and tried not to single her out but it still keeps happening. What would you do? My dh thinks we should put a lock on the snack cupboard so we can monitor their eating and they can only have when they ask. Our shopping bill is soaring at the minute. I dont know what to do or how to deal with it. Any advice would be great 