An heir hired years ago
Franquito is Dennis’s paid accomplice. The supposed family connection has already helped Dennis extract money from Frank.
Supporting source ↗CASE FILE · S10 E09
Frank Retires
S10 E09Photograph not available
After Frank decides he's worked long enough, the rest of the gang strategizes amongst and against each other for control over "Paddy's".
THE SHORT VERSION · SPOILERS AHEAD
INSIDE THE CASE.
The sample cannot answer
The bucket mixes multiple people’s blood with animal traces, leaving Charlie’s paternity unresolved.
Supporting source ↗Paperwork meets furniture
A paper plate governs the contest for an ordinary office chair, elevated into a symbol of control.
Supporting source ↗Retirement changes Frank’s appearance
His energetic exercise gives way to gray hair, pallor and a scooter as the blood-taking continues.
Supporting source ↗THE EVIDENCE
THINGS IN THIS EPISODE.
Characters
Charlie Kelly182 other recorded episodes
Charlie presents his purported paternity documentation.Source ↗
Dee Reynolds181 other recorded episodes
Dee holds the succession agreement.Source ↗
Dennis Reynolds178 other recorded episodes
Dennis introduces the supposed heir.Source ↗
Frank Reynolds173 other recorded episodes
Frank returns looking pale and exhausted.Source ↗
The doctor rejects the contaminated blood sample.Source ↗
Locations
Charlie’s apartment49 other recorded episodes
Frank exercises during his brief retirement.Source ↗
Paddy’s Pub148 other recorded episodes
The ownership confrontation unfolds at Paddy’s.Source ↗
Objects
Dee’s birth record supports her claim to being firstborn.Source ↗
Charlie’s blood bucket1 other recorded episode
A metal bucket of blood sits on the doctor’s desk.Source ↗
Hot plates2 other recorded episodes
The portable cooking surface serves Charlie’s kitchenette.Source ↗
The succession rules are written on a paper plate.Source ↗
Dennis investigates the smell of the office chair.Source ↗
Food & drinks
Albani berries1 other recorded episode
Frank has eaten Dee’s remaining scheme berries.Source ↗
Charlie prepares Frank’s breakfast at the hot plate.Source ↗
Schemes
Mac injures his hand while attempting a pledge.Source ↗
Running jokes
Charlie’s illiteracy22 other recorded episodes
The blood signature misspells Charlie’s name.Source ↗
Mac announces his supposedly secret strategy.Source ↗
Charlie explains the unusual signature on the agreement.Source ↗
Costumes
Improvised bandages3 other recorded episodes
A makeshift wrap covers Mac’s hand.Source ↗
Miscellaneous
Paternity tests2 other recorded episodes
Mac and Charlie bring a bucket as their test sample.Source ↗
FOLLOW THE THREAD
CONNECTED EPISODES.
S09 E04 Connected through Albani berries, Charlie’s apartment, Paddy’s Pub and 5 more.
S07 E04 
Connected through Scooters, Paddy’s Pub, Frank Reynolds and 4 more.
S10 E08 
Connected through Charlie’s blood bucket, Paddy’s Pub, Frank Reynolds and 4 more.
S03 E01 Connected through Paternity tests, Charlie’s illiteracy, Charlie’s apartment and 6 more.
SOURCES & NOTES.
Tags document researched occurrences, not every appearance. Read the research notes and attribution.