Cepheus is jealous

Cepheus is beginning to isolate the difference between himself and Calyce, and now i have to re-educate him on that.  Whilst my MIL is busy with cooking and Dear is sick in bed, Cepheus is always seeking attention, whenever Calyce cry and he saw that i am carrying her, he will almost cry immediately after that and cries for Daddy or my MIL to carry him as well.  And with him sticking around them whole day, it is quite impossible for my MIL to cook and for Daddy to have a good rest.  I have to talk sense to him in order to stop his tantrums.  But the replies he gave me is appalling and made me realise that he is feeling very insecure and out of place now.  Recently, Cepheus have been isolating and segregating between himself and Calyce, i keep emphasizing to him that mommy and daddy still loves him and Calyce loves him too.  However, i have neglected the point that Calyce and Mommy still belongs to him as well. He is now segregating and telling us that Daddy and Granny 'belongs' to him whereas Mommy is Calyce's. I have a shock when he actually said that a while ago.  All along he was jealous that i couldnt carry him and that all my attention was on Calyce that he have thought he have already 'lost' his Mommy and thus do not want to lose his daddy and granny.  So now, he is not allowing Daddy and Granny to go near Calyce and only Mommy can go near her.  However, he is generous and doting towards Calyce as well as he will 'sayang' Calyce and tell Mommy to make milk for Calyce when she cries.  However, no other people in the house could get near to Calyce.  I felt sad at hearing that and realise that i probably did not do a good job in preparing him to accept Calyce totally.  I sat down with him and told him softly that Daddy, Mommy and Granny all belongs to Calyce and Cepheus and even Calyce also belongs to Cepheus.  He shouldn't isolate Mommy with Calyce and Daddy with Cepheus at all.  He hang his head down while listening but did not made much of a response.  Ever since Calyce was born, i tried not to carry him as i wasnt supposed to.  I tried once while he was throwing tantrum and my wound hurts after that.  However, now i realise that he may take me not able to carry him as an indication that i do not want him anymore and thus losing Mommy forever to MeiMei and thus he was even far more over defensive over seeking attention from Daddy and Granny.

I sat through an Elmo video with him and talk softly to him at the same time re-emphasizing that Mommy belongs to both Calyce and Cepheus.  He felt happier after that and accepted my cuddles for that moment. Then when Granny was carrying him just now when grandpa came, i tried to ask him if Mommy can carry him out to meet grandpa at the door.  He paused for a moment and finally agreed and reached out his arms to me.  I immed carried him over and kissed him and handed him over to grandpa as i am not supposed to carry him for long or at all now.  I do not want him to feel left out and i felt guilty that i did not do a good job in making him feel that he is in control of the situation since Calyce was born.  He also have been throwing tantrums more than usual these days probably due to attention seeking as well as mommy is always focusing on meimei.

I will do my best to make him understand that he haven't lost Mommy to Calyce at all and that both Mommy and Calyce will love him as much and more than before, and hopefully it works.. if it means that he needs my love and security by carrying him, i will do that too as long as that helps..