Not if they've only just met. It can be a traumatic experience for a child in a separation to be introduced to their parent(s) potential new partner(s). The relationship should run at least three months to see if there is a future, before introducing the new partner to a child.
It's also important to remember that legally when it's Part 1 who has the child, Part 2 can not dictate who the child is allowed to see. And the other way around. Moving on and introducing new partners is a part of life.
In most cases, your sister's mother is also your mother, and her husband is your father. If you and your baby sister have the same father but different mothers, your sister's mother's father is your father. If you and you sister have the same mother but different fathers, your baby sister's father is your step-father if he is married to your mother.
Many women see their partners (sexual or not sexual) as a father figure. My wife sees me as a lover, friend, father figure and more. Some men also see their female partners as mother figures!
Since the father and mother each contribute half (23 chromosomes) of the genetic material needed to form a child (46 chromosomes), the brother and sister are equal in terms of biological similarity, no matter if they had a different mother (same father) or father (same mother). However, if any of the father/mother pairs are related, the result is skewed.
A parent can be a father or a mother. A mother is a female who has given birth to offspring
yes
In the Sahaptin languages that include Yakima (Yakama), a father's mother is ála.A mother's mother is káła.There are completely different words expressing "mymother's mother" or "my father's mother".
Father or Mother
A grandpa is a grandfather, the father of your father or mother.
Your half-sister's mother may be your mother, if you have different fathers. If you have different mothers and your father is married to your half-sister's mother, then you probably should call her "mother." If your half-sister's mother is not connected to your father (i.e. her father married your mother) then there is no relationship name for you to call her mother, other than "my half-sister's mother."
If the father and mother are deer, the mother would be called a doe and the offspring would be called fawns, but the answer might be different for species other than deer.
Just call him by his regular name. It is know different from any other person. He just happened to be the kid of the mother/father your mother/father would be marrying.
The father's lineage is what generally counts.