How can you raise five/six children?

I'm doing the LTW to raise five kids from baby to teen on one of my saves. I took a break to rebuild the town however and plan to continue it after.

So far the family is the parents, a fairy, Derek, and human, Rosalie; plus Rosalie's sister Juliette, then the kids: The family heir, Eduardo, who is human (currently a toddler, who's completely trained in walk, talk and potty); the twins, Lacey, who is a fairy, and Willow, who is human (toddlers, neither are trained in their skills yet as far as I know); and the newborn who's name I already forgot, who is human. I still need one more for the LTW and it's already a handful and many days of my sims having sleepness nights. Right now my sims have the perfect jobs for this though: singer, artist and private-I. Derek just recently switched from the theater music career to the Showtime Singer career. (My fault for that: I demolished the theater to rebuild Mirabello Plaza. It will return in a new location soon.)

So yes, it is possible. I recommend the sims have jobs that don't require them constantly being on the job in rabbitholes (example: Singer, Magician, Acrobat, Self-employed jobs like Artist or Author; Private Investigator, Ghost Hunter, Stylist, Architect, maybe Firefighter or Medical but medical results in too many late night emergency calls on already sleepless nights. Might be best to switch to that if the kids are older and don't require constant care). And like others said, add a sibling or a nanny sim to help out. Even better, save up simoleons to get bonehilda if your sims aren't cowards. Otherwise, if you don't have Supernatural do the maid service and cancel it later on. LOL
Also make sure your house has space so your sims won't get stuck waiting for others to move.
And a big nursery. Or two. Close to the parents' room of course.

By everything available available for the toddlers and kids. It keeps them busy while the parents focus on the younger children and their skills. Also inviting family members to "help" works wonders. It gets a bit quirky, i love it.

I have the age span on 2 days for babies as you just can't do anything with them so that shortens the time you need to care for them a little bit. I also have toddler on 5 days so the mum can spend her maternity leave teaching the toddler their skills so by the time they go back to work they don't have to rush around after work teaching skills. I also use the walker from the sims 3 store so toddlers can teach themselves how to walk. I also recommend waiting until a toddler ages up into a child or has at least learned all of their skills and is close to ageing up before trying for another baby (or try for a baby 2-3 days before they age up so that their a child when the new baby(s) arrive) this just takes the pressure off a little as kids don't really need taking care of except for a few social interactions to prevent them being taken away.

I can't even manage raising one children let alone multiple of them, they even still crying when their motives are green uggh

I love big families in the sims games. The busier they keep me the better. My main sim in my family has the life time wish to raise five children to teen and I'm planning on fulling that wish. :D

@izecson I used to feel the same way about raising kids in Sims 3. It was only within the last 2 years or so that I decided to challenge myself a little by starting out with just having one baby and raising it to a child before having another baby. It helped a lot that I had all the expansions installed and I did what I wanted to with the young adults first and didn't let anybody age until I was ready for them to start aging. That was when both of the parents-to-be were at the top of their chosen careers or they had plenty of money to take time off of work for raising the kids. Now, I've successfully raised up to 4 kids in 2 different stages at the same time without pausing aging first. The first in-game birth is always the hardest for me - especially when it's a legacy challenge game on default normal aging settings.

@Nikkei_Simmer I do that too. Though, as I said in a previous comment, I might send one or two kids of my sims to boarding school.