My two-year-old (who we’ve had from 9 weeks) has started barking to be let out during the night. This is a reasonably recent thing, probably over the past few months. Sometimes we can ignore her and she eventually stops but other times we’re having to get up at (eg) 3am and let her out. A lot of the time she does a wee but occasionally she just sits on the patio with her ears blowing in the breeze 
which is rather annoying! She’s always let out last thing before we go to bed and is perfectly capable of lasting the night. The barking is probably once or twice a week. We have a baby due in a couple of months and I’m not sure I can cope with both of them waking me up! Any ideas what this might be and how I can stop it happening?!