I think that sounds like my boy was at that age. If your HV is happy and its a baby led routine then I think its ok. MIL's info's are usually 20 years expired!! lol Most people would cut their arm off for that routine. Plus their wee routines alter constantly, so might not be the same in a months time.
When I had my daughter (who's now 3 ) she started sleeping through the night from about 6 weeks. My HV was quite happy with her routine & she put weight on normally and was healthy.
You carry on doing what your doing. If your happy & baby's well & happy too it doesn't matter what anyone else thinks.
I could tell you a few stories about comments from my MIL but wouldn't want to go on & on....lol
Sounds absolutely fine and if it's fine with you than MIL can butt out. My LO started sleeping through the night at 6 months but was never much of a daytime sleeper but I felt that me getting a good night's sleep was more important than getting house jobs done. (She also used to feed fairly regularly). I now have a contented 2 year old who sleeps from 7.30pm - 6.30am. Has one good sleep of about 60 - 90mins in the middle of the day - eats well and is very happy. You just need to do what is good for you and try not to listen to MIL's who can't really remember what it was like to have a baby.
As foofanmummy said before, MIL knowledge will be about 20 years out of date. My MIL said she used to put rice in baby's bottle to bulk it up if it kept feeding because it was hungry! She also told us that she used to cellotape the babies ears down to stop them sticking out when they were older needless to say, we don't call on her for baby-sitting!!
You are right. Follow your babies lead and you will have a happy, contented little munchkin. Trying to force a baby into a routine will only upset her. My daughter had colic and everyone told me that forcing her into a routine would 'sort her out'. I didnt listen and now my 11 month old is a happy, contented almost toddler who spends most of her day giggling and smiling. xx