Thank you everyone who suggested names for my mystery plant. Opinions were divided between the happy wanderer, (Hardenbergia violacea), and native indigo, (Indigofera australis) with an honourable mention to Tania's suggestion of 'Pinkus Wotsitus'.For the horticulturally minded, the secret was all in the leaves. Happy Wanderer has punchy large leaves to the native indigo's discreet, slightly hinged version. After a close examination of the happy wanderer in my garden, which, just quietly is neither happy nor wandering, I'm sure that Ms Mystery, (all plants, like boats are female in my mind), is Indigofera australis. Interestingly it is said that boiling the stems of the plant invokes an indigo like substance, (hence the name), which I will not be able to resist trying. Particularly as it will come in handy when I get around to finishing this project currently spending quality time on the backburner.
Janet was leading the indigofera australis charge and will be recompensed for her labours with a package of oddly familiar peggies winging their way southward whenever she can locate a photo of all family members together. Thanks again for all the helpful suggestions. I've said it before but you people are the business.
I'll leave you with my favourite stage in children's artistic development, the disembodied head, (I'm the one on the right sporting the mohawk). xx