cQuents, 93 89 bytes

| #20&bk)~" Shark"~(" doo"6,Z,Z,bk)~" Shark!" :"Baby","Daddy","Mommy","Grandpa","Grandma" 

Try it online!

Note that as of posting TIO is not updated to the latest version, so the TIO link may not work.

##Explanation

| Set delimiter to newline #20 n = 20 & Output first n terms in sequence k = 1 First term is bk)~" Shark" kth term from the third line concatenated to " Shark" ~(" doo"6, concatenated to " doo" repeated 6 times Z,Z, Second and third terms equal the first term bk)~" Shark!" Fourth term is the kth term from the third line concatenated to " Shark!" k += 1, restart Third line 5 terms, each a string 

cQuents, 93 89 bytes

| #20&bk)~" Shark"~(" doo"6,Z,Z,bk)~" Shark!" :"Baby","Daddy","Mommy","Grandpa","Grandma" 

Try it online!

Note that as of posting TIO is not updated to the latest version, so the TIO link may not work.

Explanation

| Set delimiter to newline #20 n = 20 & Output first n terms in sequence k = 1 First term is bk)~" Shark" kth term from the third line concatenated to " Shark" ~(" doo"6, concatenated to " doo" repeated 6 times Z,Z, Second and third terms equal the first term bk)~" Shark!" Fourth term is the kth term from the third line concatenated to " Shark!" k += 1, restart Third line 5 terms, each a string 

cQuents, 93 89 bytes

| #20&bk)~" Shark"~(" doo"6,Z,Z,bk)~" Shark!" :"Baby","Daddy","Mommy","Grandpa","Grandma" 

Try it online!

Explanation incoming. Note that as of posting TIO is not updated to the latest version, so the TIO link may not work.

cQuents, 93 89 bytes

| #20&bk)~" Shark"~(" doo"6,Z,Z,bk)~" Shark!" :"Baby","Daddy","Mommy","Grandpa","Grandma" 

Try it online!

Note that as of posting TIO is not updated to the latest version, so the TIO link may not work.

##Explanation

| Set delimiter to newline #20 n = 20 & Output first n terms in sequence k = 1 First term is bk)~" Shark" kth term from the third line concatenated to " Shark" ~(" doo"6, concatenated to " doo" repeated 6 times Z,Z, Second and third terms equal the first term bk)~" Shark!" Fourth term is the kth term from the third line concatenated to " Shark!" k += 1, restart Third line 5 terms, each a string 

cQuents, 93 bytes

| #20&bk)~" Shark"~(b6)6,Z,Z,ck)~" Shark!" :"Baby","Daddy","Mommy","Grandpa","Grandma"," doo" 

Try it online!

Explanation incoming. Note that as of posting TIO is not updated to the latest version, so the TIO link may not work.

cQuents, 93 89 bytes

| #20&bk)~" Shark"~(" doo"6,Z,Z,bk)~" Shark!" :"Baby","Daddy","Mommy","Grandpa","Grandma" 

Try it online!

Explanation incoming. Note that as of posting TIO is not updated to the latest version, so the TIO link may not work.