You are over-thinking it. No Eval needed. This code produces your output: 
perl -E "my $ref2 = q|parent_ref|; for my $i(0..4){say qq|first_string
+ ref[$i] second_string $ref2.ref[$i] third_string|}"

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In reply to Re: Evaluating variables within a string by NetWallah
in thread Evaluating variables within a string by smknjoe

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