okay hunny, I will see if I can help with some suggestions for you.
Is there a way you can have her near you while you are getting your 8yr old ready for school?
What about giving her solids for her first am feed? Maybe having her full early in the am could help her sllep longer for her first nap, and then that may help swing the rest of th day into order.
The one thing that I try to remember is that the need the calories during the day in order to sleep more/longer at night.
One thing I do for Riley in the afternoon is I make sure she was up at least 2 or 2.5 hrs before her bedtime, no later, and from when she wakes for a nap to when she goes to bed I cluster feed, maybe every 1.5 or 2 hrs, whatever riley feels the need to do.
When starting a new routine, I try to write it all down, what order things are in, how long or how much a feed is, how long she plays for, how many attempts and how fussy she is at naptimes. Also you can keep track of how long each cycle of the routine is and how long naps are etc. It is the only way I can keep track at times.
Your lo may need some more stimulating activity during the day, maybe rolling on the floor, something that can make her tired to go to sleep.
Are you trying a wind down before naps, I am such a sucker for not doing that and then I wonder why she is mad when I put her down.
So lets say in hindsight that she wakes at 7am and bedtime is 7pm, maybe you could work towards something like this....
E-7am-solids maybe a little bottle if she will take it
A-whatever, maybe rolling on a bed while you get you eldest dressed
E-bottle if she didn't take it before
A-TV time with mummy, or whatever takes your fancy
S-9am
I usually concentrate on the order after the first cycle as each of my days is never the same.
E-Bottle/Solids, if you feel she maybe ready for more
A-
E-alternate with whatever she didn't have for her last feed
A-
S
By this time it should be about 1pm or so, once you have the kinks out in your routine,what I normally do is keep dd up, but where your dd is 4mths, maybe let her nap at say no later than 4:30 or so, and then that way if you control when she wakes she maybe tired enough to go to bed at the right time. Also one thing I found that worked for me was a dreamfeed, I started at 11pm, and then when she started waking for it I would pull it back by a half hour or so. It may take a week or so for the df to be effective in her routine, but it is worth it.
Have you tried going on an EASY thread for the month your dd was born in, the ladies on there will most probably have some wonderful thoughts and reassurance for you too, and also help you to iron any kinks out that may crop up.
Sorry that this is so long, but I know how frustrating it can be to get the routine figured out.
I hope some of this helps you, let me know if you need more ideas.
Good Luck, remember we are only a post away if you need any of us!!!!