You’re jealous a child loves and wants to be around his birth mom? I’d say let that one go. Disengaging will help if you tend to get enmeshed. The child needs you to put up good boundaries. Let him love his mom without having to worry that you’re jealous. 

They tell to love SK like your own. But SK keep reminding you they are not yours.  Nothing you can do, you have to disengage some.  Not spending every minute you can with SS.  You have to thing and go away with DH without SS.  Or you are going to go crazy, 

My three year old grandson cries every time my son and daughter-in-law pick him up from our house. He said on Tuesday that he wants to live with grandma and pop. His best friend (and cousin) is also here and they are only ten months apart. Kids that age tend to pick favorites. It could be a parent, grandparent, or other relative or friend. Right now he just wants more than 10% of mom's time and attention. It's okay. Keep doing what you are doing and let mom do what mom does. 

Jealousy is a normal feeling and not only do we hate what makes us jealous, but we hate the fact that we ARE jealous!

Try to keep it in perspective -- the kid is really little and doesn't realize what messages you're taking from his behavior. When he's older, all your hard work (hopefully!) will pay off.

How he reacts likely has more to do with his age and relationship to his mom than anything you're doing or not doing. He will always have something special with her because it's his mom. You've always been there and you'll keep being there and maybe with luck he'll have a special bond with you too -- but it will always be different than what he has with his mom. You've probably read on here posts from people whose skids are great, but they just can't love them the way they do their own kids. This is that.

SS-3 is parroting what he is being told while on WombClan visitation.  His vocalizations are not his own thoughts or words.  He is being toxically seeded by his BM et al.

So, don’t get butt hurt over it.  Go on the full offensive to destroy this crap from BM.

Start talking about it with YOUR son “Who told you to say that sweetheart?” Etc......

Ask him about how much fun he had with you and his daddy when you did A,B, C and LMNOP...... together.

As he progresses through childhood start to share the facts and reality regarding WombClan toxic manipulations.  Review the CO with him.  Review any county supplemental rules and state regulations regarding visitation and support.  Review the court records and blended family opposition arrest records, etc.....

When he spouts about wanting to live with mommy tell him “you get to live with daddy because the court has ruled that it is better for you but you get to visit mommy”

We developed this strategy to counter the toxicity of my SS’s SpermClan.  As he progressed through his teens we frequently found him digging through the records in our two file cabinets containing the eventual 18 years of files documenting the history of his COs and the behaviors of his SpermClan when he would return home from a SpermLand Visitation to determine the truth about something the SpermClan tried to pull that didn’t pass the smell test.

Stick to the facts.

Good luck

I completely get where you're coming from. You don't want to be jealous, but it's hard when you put in all the work and get zero appreciation. I deal with this all the time. My sd is 5, lived with bm until she was 4 and then bm got tired of her and wanted to live with her now ex again, but because of accusations towards her inlaws our children could not go there. Now she has severe abandonment issues, and will randomly cry for her "real mom". It kills me, but I know it's due to what her mom did. 

I agree with the post above. For right now, remind him of all the fun you have while you're together. Never talk negatively about BM though, as it will only brew resentment towards you. As he gets older share facts, and I mean cold hard on paper facts, with him to reverse whatever alienation bm is attempting to do. Around here, age of consent (when they are allowed to have a say in their living situation and what not) is ten, but we started giving ss facts and such this year, and he is 8. Kids are smarter than what we think, and if hes anything like my ss, he will see everything on his own way earlier than that. Just hang in there, and in about two years he will begin to start seeing the subtle differences in homes. 

Always remember that kids will say anything they can to get there way. Grounded? Yep want to go to other parents because they don't care what I do. Don't get something at the store? Well my other parent will buy me anything so I want them now. Rules and structure? Yeah they don't like those, so other parent it is. It's another reason my sd only cries for BM at night, because bedtime didnt exist and tv was always optional. It's not here, and that's not ok with her. 

Another thing I want to point out really quick is kids learn from our actions. You want to fix the getting everything they want problem? Then you don't try to do anything to make them happy when they are upset. He wants to be with mom and acts like she is his favorite? Then you go along with it. Don't give the attitude the attention. Say I'm sorry that's how you feel sweetie and move on to something else. And when I say something else I mean chores, not talking about something else in general. Then, after he has time to calm himself down and get away from that idea, you ask how he liked doing a,b, and c with you and dad. Ask him what adventure he wants to do next with you two. Keep that stuff separate from the I want mom talk, or he will see a link in the reaction and go with it.