remember only one command i made one paste this command in a command block and you get baby mob spawn eggs
/give @p minecraft:oak_sign{BlockEntityTag:{Text1:'{"text":"baby eggs","clickEvent":{"action":"run_command","value":"give @p creeper_spawn_egg{EntityTag:{id:\\"minecraft:zombie\\",CustomName:\\"\\\\\\"Creeper baby\\\\\\"\\",CustomNameVisible:1,LeftHanded:1,Health:10,Attributes:[{Name:\\"generic.maxHealth\\",Base:10},{Name:\\"generic.attackDamage\\",Base:2}],IsBaby:1,ArmorItems:[{id:\\"minecraft:leather_boots\\",tag:{display:{color:4235299}},Count:1},{id:\\"minecraft:leather_leggings\\",tag:{display:{color:3055670}},Count:1},{id:\\"minecraft:leather_chestplate\\",tag:{display:{color:4783931}},Count:1},{id:\\"minecraft:creeper_head\\",Count:1}],ActiveEffects:[{Id:14,Amplifier:0,Duration:2147483647}]}}"},"color":"green"}',Text2:'{"text":"","clickEvent":{"action":"run_command","value":"give @p enderman_spawn_egg{EntityTag:{id:\\"minecraft:zombie\\",CustomName:\\"\\\\\\"Enderman baby\\\\\\"\\",CustomNameVisible:1,Health:5,Attributes:[{Name:\\"generic.maxHealth\\",Base:5},{Name:\\"generic.attackDamage\\",Base:7}],IsBaby:1,HandItems:[{id:\\"minecraft:black_wool\\",Count:1},{id:\\"minecraft:black_wool\\",Count:1}],ArmorItems:[{id:\\"minecraft:leather_boots\\",tag:{display:{color:0}},Count:1},{id:\\"minecraft:leather_leggings\\",tag:{display:{color:0}},Count:1},{id:\\"minecraft:leather_chestplate\\",tag:{display:{color:0}},Count:1},{id:\\"minecraft:player_head\\",tag:{SkullOwner:MHF_Enderman},Count:1}]}}"}}',Text3:'{"text":"","clickEvent":{"action":"run_command","value":"give @p skeleton_spawn_egg{EntityTag:{id:\\"minecraft:zombie\\",CustomName:\\"\\\\\\"skeleton baby\\\\\\"\\",CustomNameVisible:1,Health:4,Attributes:[{Name:\\"generic.maxHealth\\",Base:4},{Name:\\"generic.attackDamage\\",Base:2}],IsBaby:1,HandItems:[{id:\\"minecraft:bow\\",Count:1},{id:\\"minecraft:light_gray_wool\\",Count:1}],HandDropChances:[​0.05F,0F],ArmorItems:[{id:\\"minecraft:leather_boots\\",tag:{display:{color:2633260}},Count:1},{id:\\"minecraft:leather_leggings\\",tag:{display:{color:3683909}},Count:1},{id:\\"minecraft:leather_chestplate\\",tag:{display:{color:3551282}},Count:1},{id:\\"minecraft:skeleton_skull\\",Count:1}]}}"}}',Text4:'{"text":"","clickEvent":{"action":"run_command","value":"give @p phantom_spawn_egg{EntityTag:{id:\\"minecraft:zombie\\",CustomName:\\"\\\\\\"phantom baby\\\\\\"\\",CustomNameVisible:1,NoGravity:1b,IsBaby:1,HandItems:[{id:\\"minecraft:black_banner\\",Count:1},{id:\\"minecraft:black_banner\\",Count:1}],ArmorItems:[{id:\\"minecraft:leather_boots\\",tag:{display:{color:4946}},Count:1},{id:\\"minecraft:leather_leggings\\",tag:{display:{color:4946}},Count:1},{Count:1,id:\\"minecraft:leather_chestplate\\",tag:{display:{color:198456}}},{id:\\"minecraft:player_head\\",tag:{SkullOwner:Violit},Count:1}],ArmorDropChances:[​0F,0F,0.01F,0F]}}"}}'},display:{Name:'{"text":"Custom Sign"}'}}
i would put this somewhere elese but only one commands arent datapacks so
also this only workds 1.14