Medibank membership gets you a discount I believe.
Their policy doesn’t appear to have an age restriction for travel cancellation due to the injury of a relative… but they have other criteria:
Health of other people impacting Your travel
(non-traveller)
This policy has cover if You need to change Your trip due to the health of a Relative or Your business partner who is not travelling. In some circumstances the maximum We will pay is $1,000.
What Is Covered?
We will pay for claims arising from the sudden disabling injury, sickness or disease or death of a Relative or Your business partner who is not travelling if, at the Relevant Time, that person:
a. in the last 12 months, had not been hospitalised (including day surgery or emergency department attendance) for a condition that was in any way related to, or exacerbated by, the condition that gave rise to the claim;
b. was not residing in a facility such as a nursing home, an aged care facility, a residential aged care home, a high and/or low care facility, a privately owned accommodation facility such as Supported Residential Services or Facilities (SRS/SRF) or, a residential care facility);
c. was residing independently at home or in a retirement home or village, including independent living arrangements, and they did not require home care or flexible care services;
d. was not on a waiting list for, or did not know they needed surgery, inpatient treatment or tests at a hospital or clinic;
e. did not have a drug or alcohol addiction; and
f. did not have a Terminal Illness.