It has been really fun for us having two children so far. I think it's better than having one, honestly.
I know some moms have a hard time (feel guilty) with having the second child because they feel things like:
-the older child is cheated by not getting as much attention from the parents anymore
-the older child has to grow up faster
While, having a new baby makes my older son (he is 3 1/2 years old now) seem a lot bigger in comparison, I think that it's really unhealthy to "feel sorry" for the older sibling having to share the parents. I try not to project that attitude at all. Maybe that's because I'm the oldest child in my family. I can relate to the "trials of the eldest" and how having a new sibling can really "rain on your parade" at first so I do have an understanding and compassion for my son but I just keep the attitude that a younger sister is going to be one of the best blessings in his life from here on out and there is no need for pity.
I read a book (the only book of it's kind I could find) written for parents thinking of having a second child (this was almost a year before I fell pregnant with my second) and it had a lot of practical tips for preparing for the second child such as making sure the first child has a more developed social reach (through school, playgroups etc.) before the second child arrives so that their life remains somewhat stable even though the attention of the adults in the home is scattered. I think that this was the most helpful tip I read.
It has made my son's adjustment quite smooth (my daughter is 7 weeks old now, BTW). Because he has his "own little life" outside of just family life it makes the day-to-day adjustment of having to share his parents easier on him. He goes to kindergarten half-days, five days/week and also takes sports classes at the YMCA in the afternoons a few times/week. (He loves sports!) He also continues to spend time with his grandparents on the weekend and then during the other days of the week he has special "date nights" with his parents (For example, his dadda will take him out to play basketball and eat sushi once or twice a week or take him on a picnic and hike in the hills). The rhythm of his schedule makes him feel more secure and less fussy.
Also, he LOVES his little sister and calls her "my BB." He'll ask, "Where's my BB? I want to see my BB." He is always gentle with her and likes to bring her toys to play with or cover her up with a blanket. Recently he has started to help us give her a bath in the evening. His job is to wash her feet (something we know he can do but won't end up pouring water in her mouth etc.). He really feels like a vital part of her care and our family.
With a little baby to take care of, I don't have the same amount of energy I had before to fully spend on my son but I do make sure we keep a habit--I put him to bed at night. I spend time cuddling with him, talking to him, tickling him and reading to him. It's not a large amount of time anymore but it's 100% quality time and I know my little boy knows he's loved and needed in our family. Sometimes I have to go out of the room to breastfeed the baby and he'll say, "You come back and cuddle me later?" So, this actually teaches my son patience and how to share--he knows he has to wait if the baby needs to be fed but he is adjusting well.
Having said all this, I think you'll find that how well the adjustment goes depends on many factors--including the personality of your older child. Also, my son was quite mentally prepared for a younger sibling. He already had a relationship with his younger sister long before she was born as he would often lay his head on my belly and try to listen for the baby or even talk to her. Little children are much smarter than we give them credit for. I think talking a lot about the new baby with your older child and just making them a part of the experience in age-appropriate ways (i.e. allowing them to pick out toys or clothes for the baby etc.) is the best way to ensure a smoother transition.
