I have father's data
id household member number father's age ..other father's variables parent-child identifier
70870323 1 50 1
80820109 3 60 2
100650216 1 46 1
191000221 14 75 1
250660113 3 68 3
271480203 6 79 1
I have child's data
id household member number age_child disability _level_child disability_duration_child parent-child identifier
70870323 1 6 2 5 year 1
70870323 2 21 3 10 year 1
80820109 3 14 4 15 year 2
80820109 4 5 4 2 year 2
100650216 5 17 2 5 year 1
100650216 6 12 4 10 year 1
191000221 9 7 3 15 year 1
250660113 10 8 4 20 year 3
271480203 14 13 2 4 year 1
I reshaped wide child's data to merge with father's data
id household member number age_child1 age_child2 age_child3 age_child4 … disability _level_child1 disability _level_child2 disability _level_child3 … disability_duration_child1 disability_duration_child2 disability_duration_child3 disability_duration_child4 parent-child identifier
70870323 1 2
80820109 3 4
100650216 5 2
191000221 9 3
250660113 10 4
271480203 14 2

I merged child's and father's data
id household member number father's age ..other father's variables parent-child identifier age_child1 age_child2 age_child3 age_child4 … disability _level_child1 disability _level_child2 disability _level_child3 … disability_duration_child1 disability_duration_child2 disability_duration_child3 disability_duration_child4 parent-child identifier
2
70870323 1 50 1 3
80820109 3 60 2 4
100650216 1 46 1 4
191000221 14 75 1 2
250660113 3 68 3 4
271480203 6 79 1 3

Now, I want to use data of only that child from among multiple children of same ftaher, use only those data for children with highest level of disability. If the disability level of 2 child of same father is same, use data of that child with highest duration of disability of child. Please let me know how may I do so.