What is the ruling on filming supplications for family in front of the Kaaba and publishing them to make the recipients happy, and what is the ruling on concealing an ‘Umrah trip from friends with the intention of devoting oneself to worship and avoiding ostentation?

The basic principle concerning supererogatory acts of worship (nawafil) is to conceal them as much as possible, as this is more conducive to sincerity and further removed from ostentation (riya') and seeking reputation (sum'ah). Writing a supplication for others, photographing it in front of the Kaaba, and publishing it is not forbidden, but it may open doors for Satan, such as showing off to people, seeking status, and soliciting their praise through worship. Therefore, it is more appropriate to avoid this to safeguard one's worship.