Having hummed and haaed for several months (DS is 9 mnths old -how?), I was just about to order a new cot mattress with springs for Ds cot when DH said 'won't he need a bed soon?'. Surely not? My dilemma is,do I buy a new cot mattress now and then later on put DS in a bed (when do they go in a bed?) or scrap the cot and buy a cot bed now? or will the cot bed not last much longer.Please can anyone advise on the maximum age for moving from cot to bed or does it depend on athleticism of DS?