Tsuma, Shougakusei ni Naru.

Both shows have a similar premise where someone in the family becomes younger. ('Reincarnation' being the main plot element for TsumaSho; whereas Jiisan Baasan has spiritual/supernatural elements). The common recurring theme in both shows is 'Second-hand Happiness'; where they proudly see their kin maturing becoming upstanding people as they face challenges in becoming an adult. And helping them face those challenges when needed.  

Somebody special to the main character has passed away, but miraculously they are given a second chance. The person comes back to life, and this time, they do everything they can to cherish and protect their loved ones. The settings differ, as Tsuma is family-themed while Orange focuses on school life, but both are emotional and have a dark twist.  

Both anime focus on a loving father and his caring family, showing how far they will go for each other. Although the plots are different, they both share a strong theme of family. At first, the stories seem wholesome and happy, but they also have a dark twist that makes it hard for the characters to live the lives they want. As they try to go back to how things used to be, they realize it’s much harder than they expected. They're both very refreshing, unique animes 

Both involving main character losing their lover, but were given a second chance to rebuild the relationship, coping with grief, and moving forward  

At first glance, these anime are not much alike, but the sensations when watching are the same. Both series deceive the viewer's expectations. The story begins as a joke on the verge of a foul, but in fact it is a drama about children and parents who are trying to restore a once-damaged relationship 

Both Ginban Kaleidoscope and Shinigami no Ballad explore themes of romance, drama, and the lingering presence of spirits. In Ginban Kaleidoscope, a figure skater is haunted and possessed by a male spirit, complicating her life and ambitions. Similarly, tsuma follows a mother reincarnated as a child to reunite with her husband and daughter. Both stories revolve around navigating life alongside restless souls while facing an uncertain future. 

Despite some supernatural elements (mythology magic/ "reincarnation" respectively); both of these shows contain themes of filial-drama such as a death of a family member, single parenting issues, domestic abuse and second-hand happiness due to the altruistic nature of the main character. TsumaSho & Fruits Basket tells a tale of bonds of family and the struggles of relationships and letting go. 

Both of these heartfelt stories are about a strong willed mother who has been given another chance at a life that was cut short and become young again much to the surprise to their family members. (Though 'reincarnation' is the main driving force for TsumaSho, whereas 「Mom I'm Sorry ！」is more supernatural.) The main crux of both shows is about the appreciation of the time spent with the family and how letting go becomes the challenge for each family. They also share some similarities with topics and themes such has single parent challenges, second-hand happiness, domestic abuse and self-martyring/altruism. 

Both shows are about the struggle to move on from the death of a loved one and to cheerish every single day you can share with the people you care. 

Both stories follow main characters dealing with the loss of their spouses, whose souls remain in the world due to unresolved feelings. In Tsumashou, a mother reincarnates as a child, unable to move on, believing her husband and child need her. In Natsuyuki Rendezvous, a husband becomes a ghost, haunting the man working alongside his wife. Both anime explore life’s uncertainties through a supernatural lens, highlighting themes of grief, coping with depression, and finding ways to move forward.