Yes, they will be pretty different for various reasons! For example, Blanca was the main person who discipline the children—and Nico—at all. Raphael killed Donte extremely young and is now quick to draw a gun for such reasons because it's the 'best way' to protect and he resented his father for a little because he thought it was his fault for not killing Donte long before. He is by nature lenient like his father to loved ones but immediately switches to violence to take no chances. This can be seen with the way he treats (his user), even agreeing to a break up for her sake if it makes her happy before starting to lose his patience. Otherwise he will probably be more level headed, slower to draw a gun but still adoring to his young siblings and a little impulsive to their whims.

In Vittore's case, while Nico was in the middle of his grief and Nico was being all edgy, he stepped up to the missing nurture role. This is why he is extremely bad at expressing his own feelings and emotions as he was focused constantly on everyone else's. He treats Raphael like a brother and is less lenient with his messes because they had more time together being just 'brothers' I. A sense. He treats Romeo and D'Angelo more gently bit also frantic like because it's like a weird hybrid of brothers/paternal instincts taken care of them when Nico was busy grieving and doing business to keep the family afloat. Out of most, he will probably be the same.

Romeo is attention starved/seeking because he is subconsciously jealous that D'Angelo is the favorite but also feels guilty of that jealousy. He doesn't know his mom too well so he cannot relate with Vittore and Romeo's talks of her. He bonds most with D'Angelo—that won't change in any life. He, like his father, is very emotional which makes his need for attention and acting out show more in his behavior (sneaking out, getting into entertainment, being a playboy, etc). If Blanca was alive, treatment would have been equal and he wouldn't have guilt or be so touch starved.

D'Angelo was born sickly due to the coma, plus his looks made him adored more. He is treated like he cannot do wrong by everyone but Romeo and the only person he truly allows to tell him he is wrong is Romeo. Every want and whim he demands is given and he's never had Blanca's discipline. He doesn't know anything about her at all and while he later gets involved in medicine and is part of the 'clean' business side with Romeo's clubs, he knows part of the mafia well as everyone is tightknit. If blanco was alive he would have been born much stronger, disciplined and loved in an equal measure that won't make him so shameless. Playing at being innocent won't work, but he'll find another way no doubt.

Morelli's bred like New York rats—there would be a lot more kids.