On the occasion of the 67th birthday of the 12th Tai Situ Rinpoche today, during his online teachings, HH 17th Gyalwang Karmapa, recited the long-life prayers for Tai Situ written by the previous Drupon Dechen Rinpoche (for more info on his life, see here).
In addition, the 17th Karmapa composed a new long-life prayer for the 12th Tai Situpa which I have translated below as follows:
jamchen tukjé gyutrul ö nang lé/
nyikdü dro la tsewé zhenwang chen/
kyilkhor künjung rik gyé khyabdak ché/
pema dön yö drubpa shyabten sol
From the great light magical display of loving compassion,
Overwhelmed by love for beings in this degenerate era,
Great Sovereign Lord, mandala source of hundreds of Buddha families,
Padma Donyo Drubpa, may you long remain!
In the western year 2021, on the special occasion of Jamgon Dorje Chang [Tai Situ Rinpoche]’s birthday, the one merely holding the name Karmapa, called Orgyen Trinley Dorje, composed this simple long-life prayer spontaneously with whatever came to mind. Sarva Mangalam!
སྤྱི་ལོ་ ༢༠༢༡ ལོར་ཀརྨ་པའི་མཚན་ཙམ་འཛིན་པ། ཨོ་རྒྱན་ཕྲིན་ལས་སུ་འབོད་པས་༧བྱམས་མགོན་རྡོ་རྗེ་འཆང་སྐུ་བལྟམས་པའི་དུས་ཁྱད་པར་ཅན་ལ། སྐུ་ཚེ་ཡུན་རིང་བརྟན་པའི་སླད་བཅོས་མིན་གྱི་བློས་གང་ཤར་སྨོན་པ་འདིས་ཀྱང་སརྦ་མངྒ་ལཾ། །
Spontaneously translated by Adele Tomlin, 19th February 2021.
Let us not forget that the great treasure-revealer, Chogyur Lingpa, revealed that Padmasambhava [Guru Rinpoche] prophesised [see here] that the 17th Karmapa would be one with mind as Tai Situ Rinpoche. Emaho!
Below is a song that the 16th Karmapa, Rigpe Dorje wrote when he was 17 years old for the 11th Tai Situ Rinpoche.
A SONG by H.H. the 16th Gyalwang Karmapa, Rangjung Rigpe Dorje (1924 – 1981)
This song is ala thala thala,
Ala is the way it arose.
Thala is the way it is expressed in words.
In a pure land, rich with turquoise leaves,
On a throne of brilliant, white shell
Is the deity of long life, the mother Lady Tara.
I pray to her from the depths of my heart.
May there be no obstacles to long life.
If you do not recognize this place,
It is the Retreat House of Palpung.
If you do not recognize a person like me,
There is the upper valley of delightful Shukra
And the lower valley of delightful Shukra;
In the place between the two Shukras
Is a child who descends from Tshazhang Denma
If you call him by name, it is Thubten Gelek. 
Not now, but on a distant tomorrow it will be decided.
Both the vulture and I know where to go.
The vulture soars into the expanse of the sky;
Our people do not stay, but go to India.
In the springtime, a cuckoo comes as a guest.
In the fall when the harvest ripens, it knows where to go:
Its only thought is travel to the east of India.
In the lofty land of Tibet, the inhabitants, high and low,
And in particular, you, Tai Situ, the Lord and
Who remains above the crown of our head,
May your activities, like the sun and moon set in space,
Be continuous, stable, and without hindrance.
I pray that we meet again and again.
May the three roots–the lamas, yidams, and dakinis–
Protect him from negative conditions and obstacles.
Keep the precise meaning recorded here in the
depth of your heart.
In the sixteenth rabjung’s [sixty year cycle’s] year of the iron dragon, the sixteenth incarnation of the Karmapas, Rangjung Rigpe Dorje, composed this song when he was seventeen years old at Palpung Chökhor Ling. May it be auspicious. Under the guidance of Khenchen Thrangu Rinpoche, translated by Michele Martin of New York © April 1994.
Footnote annotations by Ven. Khenchen Thrangu Rinpoche
 This indicates the birthplace of the XVIth Karmapa, situated between the two Shukra valleys with a river flowing across one end. [note on navigating footnotes: click on footnote in body of song to view footnote reference; click on footnote reference to return to note location in body of song.]
He was one of the chief ministers of Gesar of Ling, the great Tibetan warrior and emanation of Guru Rinpoche.
 Thubten Gelek is a childhood name of the XVIth Karmapa.
 Here the Karmapa is clearly predicting the future flight of the Tibetans to India.
 Following its pattern of migration, the cuckoo comes in the spring and leaves in the fall; in this same natural way, the Karmapa knows when it is time to leave Tibet for the eastern part of India, where he will take up residence in Rumtek, Sikkim.
 The Karmapa is alluding to the fact that Tai Situ Rinpoche will meet the Karmapa again when he reincarnates as the XVIIth Karmapa, Urgyen Trinley Dorje. It is Tai Situ Rinpoche who discovered the XVIIth Karmapa and takes responsibility for him; thus they meet again and again.
 Padma Donyo Nyinche (pad+ma don yod nyin byed) born in 1954 is the 12th Tai Situpa.