ds2 is only a wk old so not planning to just yet but wanted to know if anyone knew when I could use one - used one with ds1 until 12 wks but not sure when I introduced it, I used to let him comfort on me loads to start with(which was lovely ) but this time ds1 is 18mo so I can't sit down for as long just gazing at ds2 whilst he comforts... any advice?